FIG. 7 illustrates transmission/reception timing in a Uu interface (radio base station interface) of a conventional LTE (Long Term Evolution) system.
In an example in FIG. 7, at a frequency F1, a mobile station UE is configured to receive a control signal through a PDCCH (Physical Downlink Control Channel), and to receive a data signal through a PDSCH (Physical Downlink Shared Channel).
The mobile station UE is also configured to transmit the data signal through a PUSCH (Physical Uplink Shared Channel) at a frequency F2.
A radio base station eNB is configured to transmit a “DL resource allocation” notifying of an allocation of an opportunity (Uu DL) to receive the data signal through the Uu interface (PDSCH) and a “UL grant” notifying of an allocation of an opportunity (Uu UL) to transmit the data signal through the Uu interface (PUSCH) through the PDCCH.
The “Uu DL” is allocated on a subframe identical to the PDCCH.
On the other hand, the subframe to which the “Uu UL” is allocated is determined in consideration of a processing delay until the data signal (transport block) is generated from the time when the “UL grant” is received through the PDCCH in the mobile station UE.
For example, the “Uu UL” is configured to be allocated to the subframe located behind the subframe, to which the PDCCH is allocated, by X subframes.